Viscose spinning solution



Patented Nov. 20, 1934 UNITED STATES 'PATET EFFAQE VISCOSE SPINNING SOLUTION No Drawing.

Application December 29, 1933,

Serial No. 704,514

4 Claims.

The present invention relates to a process of producing viscose filaments having light-reflecting properties differing from those produced in a conventional manner.

One object of my invention is to incorporate into viscose spinning solutions a compound which will produce an effect upon the light-reflecting qualities of the finished filaments such that they will appear to be of a duller lustre than ordinary filaments.

Another object of my present invention is to produce a viscose spinning solution which will yield filaments possessing a sheen lustre resembling that of real silk.

A third object of my invention is to incorporate a mono-thiocarbonic acid ester, a tri-thiocarbonic acid ester or a metallic salt of such esters into a viscose spinning solution to produce dull lustre filaments.

A fourth object of my invention is to produce a new delustering agent for viscose filaments, said agent comprising mono-thiocarbonic acid esters or tri-thiocarbonic acid esters of aliphatic or aromatic alcohols and of other organic compounds having reactive OH groups.

Other objects of my invention will become apparent to those skilled in the art from a study of the following specification.

When cellulose is impregnated with a mercerizing solution of caustic soda, and carbon bisulphide is subsequently added thereto, a watersoluble sodium salt of cellulose xanthogenic acid is produced. This salt is generaly called viscose, and it may readily be decomposed with the formation of gelatinized cellulose. Theoretically, during the viscose reaction, sodium cellulose xanthogenate is formed in accordance with the following equations:

(1) (C6H1005)x+NaOH= (CeI-I904-ONa) X+X(H20) have, heretofore, been used for the -manufacture of filaments, films and the like, and that U. S. Patent No. 1,937,110 of November 28, 1933 to Elssner discloses the addition of salts of dithiocarbonic acid-o-isobutyl ester, but I verily believe myself to be the first inventor to propose the addition of mono-thiocarbonic acid esters, tri-thiocarbonic acid esters and/or metallic salts of such esters as delustering agents for viscose filaments. Aliphatic alcohols, such as methyl, ethyl, propyl, butyl alcohol, etc., i. e. alcohols having the structure CnIIZn-H, aromatic alcohols and other organic compounds, such as starches, having reactive OH groups, may be treated with monoor tri-thiocarbonic acids to yield correspending esters which are adapted to be mixed singly or in combination with viscose spinning solutions in order to produce the aformentioned eifect. I have, furthermore, found that thiocarbonic acid esters, set forth above, may be treated with metal salts to produce soluble or insoluble compounds suitable as delustering agents, the solubility of the reaction product depending upon the characteristics of the specification introduced. '80

Mono-thiocarbonic acids, thiocarbonic acids and tri-thiocarbonic acids may be caused to react with aliphatic alcohols, aromatic alcohols and other organic compounds having reactive OH groups to form esters. The following table depicts a series of esters capable of modifying Viscose silk, but it is to be noted that my invention is not limited to these compounds which are merely given as examples.

Boiling point Thio-ethyl carbonic ethyl ester 156 C. Thion-carbonic acid ethyl ester 161 C. Tri-thiocarbonic methyl ester 205 C. Tri-thiocarbonic ethyl ester 240 C.

Mono-thiocarbonic starch ester, tri-thiocarbonic starch ester, etc.

the metal introduced, soluble or insoluble metal salts are formed in the viscose filaments. The nature of the alkyl group and the residual organic groups, respectively, governs the formation of organic compounds which, upon evaporation, will have the effect of reflecting light in such a manner that filaments of very dull lustre are produced. The amounts of the new delustering agents to be added to viscose may be varied within wide limits, although I have found that an admixture of about 5 to will produce very satisfactory results.

Example To a 1000 liter batch of a viscose spinning solution, containing about 7.5% cellulose and 6.8% sodium hydroxide, are added 6 kilograms of calcium mono-thiocarbonic-o-isobutyl ester.

The mixture is thoroughly stirred and spun under conventional conditions.

I wish to point out thatthecompounds, as well as their quantities to be admixed to viscose spinning solutions set forth above, are merely tion anda metal salt of an aliphatic ester of a mono-thiocarbonic acid.

4. A spinning solution for the manufacture of soft-lustre products comprising a viscose solution and a mono-thiocarbonic-o-isobutyl-ester.

RUDOLPH s. BLEY. 

